Role of ischemic modified albumin in the early diagnosis of increased intracranial pressure and brain death

AIM

Increased intracranial pressure following trauma and subsequent possible development of brain death are important factors for morbidity and mortality due to ischemic changes. We aimed to establish the role of ischemic modified albumin (IMA) in the early diagnosis of the process, starting with increased intracranial pressure and ending with brain death.

MATERIALS AND METHODS

Eighteen Wistar-Albino rats were divided into three groups; control (CG, n = 6), increased intracranial pressure (ICPG, n = 6), and brain death (BDG, n = 6). Intracranial pressure elevation and brain death were constituted with the inflation of a balloon of a Fogarty catheter in the epidural space. In all three groups, blood samples were drawn before the procedure, and at minutes 150 and 240 for IMA and malondialdehyde (MDA) analysis.

RESULTS

Serum IMA levels at 150 and 240 minutes were higher in ICPG than in CG (p < 0.05). IMA levels were similar in ICPG and BDG. Serum MDA levels at 150 and 240 minutes increased in ICPG and BDG groups compared to CG (p < 0.05). MDA levels were similar in ICP and BD groups.

CONCLUSION

IMA should be considered as a biochemical parameter in the process starting from increased intracranial pressure elevation and ending at brain death (Tab. 3, Fig. 5, Ref. 31).

The effects of dexmedetomidine on pulmonary artery pressure in experiment

AIM

The primary purpose of this study is to assess the effects of dexmedetomidine (DEX) infusion on pulmonary artery pressures (PAP), heart rate (HR), and mean arterial pressure (MAP) in pigs. The secondary purpose is to evaluate whether DEX infusion via the pulmonary artery has any beneficial effect over the peripheral IV route.

MATERIALS AND METHODS

Sixteen healthy male pigs (25-35 kg) scheduled for laparoscopy training were used in this study. The animals were randomly allocated into two groups: Group I (n = 9): A loading dose of 1 μg/kg DEX was administered over 10 minutes followed by an infusion of 0.5 μg/kg/hr for one hour via the pulmonary artery catheter. Group II (n = 7): A loading dose of 1 μg/kg DEX was administered over 10 minutes followed by an infusion of 0.5 μg/kg/hr for one hour via the peripheral venous catheter. Mean PAP, HR, MAP, SpO2, and ETCO2 were recorded at 5, 10, 15, 30, 45, and 60 minutes after the initiation of the DEX infusion.

RESULTS

Heart rate and MAP were similar in both groups at all time points. Also, neither the HR nor the MAP deviated from the basal values in Groups I and II at any time point. The mean PAP values were similar in Groups I and II, and in Group I, the mean PAP values were similar to Group I's basal value at all time points. However, in Group II, the mean PAP values at 5, 45, and 60 minutes were significantly lower than Group II's basal value (p = 0.023, p = 0.041, p = 0.015, respectively).

CONCLUSION

DEX infusion did not elevate the mean PAP and the results from the administration of DEX through the peripheral vein and pulmonary artery were similar (Tab. 3, Ref. 13).

No effect of perianal application of topical anaesthetic on patient comfort during nonsedated flexible sigmoidoscopy: a randomized, placebo-controlled clinical trial

AIM

A literature review revealed no data on the effects of topical anaesthetic on patient comfort during flexible sigmoidoscopy. We therefore aimed to evaluate this in a randomized manner.

METHOD

One hundred and forty-six patients who underwent flexible sigmoidoscopy were randomly allocated to one of three groups. Vaseline (n = 49), 2% lidocaine gel (n = 51) or a cream of 2.5% lidocaine plus 2.5% prilocaine (n = 46) were applied to the patients 30 min before the procedure. Demographic data and haemodynamic monitoring during procedures were recorded. Pain was assessed by visual analogue scale (VAS) and anxiety levels by the State-Trait Anxiety Inventory (STAI-I and STA-II).

RESULTS

Median pre-procedural STAI-I scores were 45, 46 and 40.5 and median post-procedural STAI-I scores were 35, 34 and 33.5 for the vaseline, lidocaine, and lidocaine/prilocaine treatments, respectively. There was no statistical difference among the groups in terms of STAI-I and II scores. However, post-procedural STAI-I scores were significantly lower than pre-procedural values in each group (P < 0.001). There was no significant difference in VAS scores among the groups. In all groups there were statistically higher VAS scores during the procedure compared with the pre- and post-procedural scores (P < 0.001).

CONCLUSION

Perianal application of topical anaesthetic does not influence patient comfort during sigmoidoscopy.

Commonly used intravenous anesthetics decrease bladder contractility: An in vitro study of the effects of propofol, ketamine, and midazolam on the rat bladder

Aim:

This study was designed to test the hypothesis that propofol, ketamine, and midazolam could alter the contractile activity of detrusor smooth muscle.

Materials and Methods:

Four detrusor muscle strips isolated from each rat bladder (n = 12) were placed in 4 tissue baths containing Krebs-Henseleit solution. The carbachol (10 ⁻⁸to 10⁻⁴mol/L)-induced contractile responses as well as 5, 10, 20, 30, 40, 50 Hz electrical field stimulation (EFS)-evoked contractile responses of the detrusor muscles were recorded using isometric contraction measurements. After obtaining basal responses, the in vitro effects of propofol, ketamine, midazolam (10⁻⁵ to 10⁻³ mol/L), and saline on the contractile responses of the detrusor muscle strips were recorded and evaluated.

Results:

All the 3 drugs reduced the carbachol-induced and/or EFS-evoked contractile responses of rat detrusor smooth muscles in different degrees. Midazolam (10⁻⁴ to 10⁻³ mol/L) caused a significant decrease in the contractile responses elicited by either EFS or carbachol (P=0.000−0.013). Propofol (10⁻³mol/L) caused a decrease only in EFS-evoked contractile responses (P=0.001−0.004) and ketamine (10⁻³mol/L) caused a decrease only in carbachol-induced contractile responses (P=0.001−0.034).

Conclusion:

We evaluated the effects of the 3 different intravenous anesthetics on detrusor contractile responses in vitro and found that there are possible interactions between anesthetic agents and detrusor contractile activity. The depressant effects of midazolam on the contractile activity were found to be more significant than ketamine and propofol. Despite the necessity of further studies, it could be a piece of wise advice to clinicians to keep the probable alterations due to intravenous anesthetics in mind, while evaluating the results of urodynamic studies in children under sedation.

Effects of repeated desflurane and sevoflurane anesthesia on enzymatic free radical scavanger system

BACKGROUND

To investigate the possible effects of repeated sevoflurane and desflurane anesthesia on hepatocellular system by evaluating the free radical metabolism, hepatocellular enzymes and histopatholgical changes in rats.

METHODS

Four groups of animals were studied. Sevoflurane 2% (v/v) and desflurane 6% (v/v) in air/O2 were administered to animals in group II (n=9) and III (n=9) respectively. 100% (v/v) O(2) was administered in group IV (n=9). Administration was done for 60 minutes over 3 days. Nine animals were allocated to control group (group I), superoxide dismutase (SOD), catalase (CAT), glutathion peroxidase (GSH-Px), glutathione-s-transferase (GST) and thiobarbituric acid reactive substances (TBARS) were studied. Also electron microscopy was performed.

RESULTS

Catalase, SOD, GSH-Px, GST activities and TBARS levels were significantly higher in groups II and III than in group I (p<0.05). All parameters were significantly higher in groups II versus group IV (p<0.05). On the other hand, SOD, GSH-Px and GST activities were significantly elevated in group III than IV, but CAT activity and TBARS levels were not significantly. Catalase, SOD, GSH-Px, GST but not TBARS levels were significantly higher in groups II and III than in group IV (p<0.05). TBARS levels were higher in group III than in group IV, but this elevation was not statistically significant. CAT, SOD and GSH-Px activities were significantly higher in groups II than in group III (p<0.05).

CONCLUSION

Although electron microscopy findings were similar for group II and III, we can conclude that sevoflurane might cause more cellular damage than desflurane by causing higher activation of free radical metabolising enzymes.